The present invention relates generally to electronic circuits, and in particular to amplifiers with input and output signals control.
Many electrical circuits have amplifiers for amplifying input signals to produce amplified output signals.
In most applications, the signal levels of the output signals depend on the signal levels of the input signals. And the speed of the amplifier depends on the switching of the output signals. Thus, the speed of the amplifier indirectly depends on the signal levels of the input signals.
In some applications, the input signals of the amplifier are limited to some fixed signal levels to improve the speed of the amplifier. However, in some cases, fixing the signal levels of the input signals may cause the output signals to differ from specified signal levels.
The various embodiments of the present invention provide methods and circuits for variably limiting signal levels of input signals of amplifiers based on signal levels of output signals of the amplifiers to improve the speed of the amplifying circuit.
In one aspect, a circuit includes an amplifying stage for receiving input signals to generate output signals. A swing detect unit detects signal levels of the output signals. A clamp unit variably limits signal levels of the input signals based on the detection by the swing detect unit.
In another aspect, a method of operating an amplifying circuit includes receiving input signals to generate output signals. The method further includes limiting signal levels of the input signals based on signal levels of the output signals.